Hose line for sucking off hot gases,particularly in the vacuum degassing of large metal and steel batches



March 4, 1969 A. SICKBERT 3,430,663

HOSE LINE FOR SUCKING OFF HOT GASES, PARTICULARLY IN THE VACUUM DEGASSING OF LARGE METAL AND STEEL BATCHES I of 4 Sheet Filed April 9. 1963 QLELELEZLEV March 4, 1969 A. CKBE 3,430,663

HOSE] LINE FOR SUCKING 0 HOT GA 8, PARTICULARLY IN THE VACUUM DEGASSING OF LARGE METAL AND STEEL BATCHES Filed April 9, 1963 Sheet 2 of 4 Jnvenlar:

March 4, 1969 s c 3,430,663

HOSE LINE FOR SUCKING OFF HOT GASES, RTICULARLY IN THE VACUUM DEGASSING OF LARGE METAL STEEL BATCHES Filed April 9, 1963 I Sheet Of i .70 venfor:

March 4, 1969 A. SICKBERT 3,430,663

HOSE LINE FOR SUCKING OFF HOT GASES, PARTICULARLY IN THE VACUUM DEGASSING OF LARGE METAL AND STEEL BATCHES Filed April 9, 1965 Sheet 4 of 4 INVENTOR BY ADOLF SICKBERT 7- ATTORNEYS.

United States Patent 3 Claims If degassing of molten metal, particularly of steel, is not run by means of a stationary vacuum tank, as is usually done, but by means of a transportable vacuum tank instead, particularly of a ladle arranged as a vacuum tank, using a flexible line, particularly a hose line, for connecting the transportable vacuum tank to a stationary suction line or to the pump unit will be advantageous. This applies in particular, if the molten metal, particularly steel, drops into the vacuum in the form of a jet, and that from a feed tank mounted vacuum tight on the vacuum tank. In this again, executing the process with such metal, particularly steel, immediately dropping from the melting furnace running without vacuum into the vacuum tank is of no small concern.

In this so-called tap degassing a flexible line, particularly a hose line, will be of special value as well because in many cases this kind of process requires changing the arrangement of the vacuum tank and its feed hopper respectively with regard to the melting furnace to be tapped in the course of tapping. The vacuum tanks equipped with such hoses will, furthermore, be suitable for conveying off the material collected without removing the vacuum, e.g. towards a casting place distant from the melting furnace.

Hoses showing the properties necessary in such processes have not been available so far. Obviously, the problem of developing a hose having the properties particularly required in tap degassing, has not been solved as yet. In this, requirements have to be met that are partly contradictory and, as to the invention, require certain materials and the arrangement of such materials to make allowance of the various stresses to a large extent.

According to the invention, tanks, particularly transportable vacuum tanks for degassing steel or other metals, are provided with flexible lines or hoses the walls of which comprise separate layers, the internal and external layers being spaced from one another.

The internal layer is composed of metallic members able to resist the pressure exerted on the hose line. Though connected with each other, these internal metallic members allow the hose line to be curved in all directions. The joints of the individual metallic elements of said hose line are, therefore, not vacuum tight.

The external layer of the hose line consists of an elastic material such as rubber or plastics. It may have reinforcements, e.g. annular or screw-shaped wires or threads. This elastic layer must be vacuum tight.

Finally it is necessary that the two aforesaid layers, i.e. the internal metallic bearing layer and the external vacuum tight elastic one, should be spaced from one another. This spacing of the internal and external layers can be done in one way or another and by different means. For instance, the spacer may be a layer of a heat resistant and thermal insulating material, such as asbestos, glass wool, or mineral wool, of a relatively loose condition, or metallic rings, coils, plaits or texture may assure the spacing.

The drawing shows some executions of the hose lines according to the invention as well as suitable connections ice of the hose lines to the vacuum tank and supports for the hose line end to be connected to the vacuum tank, further features of the invention likewise resulting therefrom.

FIGURE 1 shows a sectional view of a hose line comprising an internal metallic layer, an external flexible hose, and an intermediate loose layer of asbestos or the like.

FIGURES 2 and 3 show sectional views of hose lines comprising pipe members with turning or ball-and-socket joints and vacuum tight hose disposed above the pipe members, in the area of the joints at least, and spaced from pipe member and joint.

FIGURES 4 and 5 show hose lines connected to a vacuum tank, the ends of the hose lines being secured to a separate support.

FIGURES 6 and 7 show the quick coupling for connecting a hose line according to the invention to the vacuum tank socket.

FIG. 8 is similar to FIG. 2 showing a helically wound spacing means.

Referring to FIGURE 1, the wall of vacuum hose V comprises the internal metallic layer 1 being a metal hose here, the windings of which being easily displaceable against each other and not being vacuum tight. Such layer 1 .is followed by a loose, heat resistant and heat insulating layer 2, say of asbestos or mineral wool fibers, and then by the external layer, i.e. a vacuum tight sheath of a plastic material, e.g. of rubber or plastics. This external sheath is reinforced by means of steel wires 4 to oppose the external pressure tending to press sheath 3 into the windings of the internal layer. At its end, sheath 3 is pressed on a tubular end piece 5 of the internal layer, e.g. by means of pipe clips 6. At the extremity of end piece 5 a flange 7 is provided. A duct 8 passes through external sheath 3 to allow gas inhibiting combustion to be conveyed to intermediate layer 2. This duct may axially extend through intermediate layer 2 to have outlets 9 for the gas fitted at various points of the length.

Due to the structure of the internal metallic layer, this will not only resist any outer pressure exerted on the hose, but, moreover, no substantial pressing of the external layer into discontinuities of the bearing layer will be possible. Therefore the members of the internal layer such as strip or wire windings, adjacent rings or the like, should have a correspondingly smaller axial distance. On the other hand however, those members should be easily movable in axial direction to allow them, in case of bendings of the hose, to approach each other on the pressure side and, possibly, to remove themselves from one another on the tension side. Owing to the fact that in such processes, particularly in tap degassing, temperatures as high as 400 to 800 C. will occur in the hose line, the internal metal hose preferably consists of a heat resistant metal, particularly of steel.

The intermediate loose layer first serves for the thermal insulation of the external vacuum tight layer that will not withstand temperatures possible in the suction line with vacuum treatment of steel, for instance exceeding 200 C. (rubber) or being from 400 to 800 C. (plastics).

Furthermore, the intermediate loose layer supports the flexibility of the hose. Lubricants such as talc or the like there inserted will additionally assist this. Moreover, materials such as talc are not combustible. If equipped with reinforcing elements, the external layer should preferably have such elements spaced from each other, e.g. in the form of windings or rings.

Instead of providing one internal layer and one external layer each time, there may be arranged several such layers. In big steel degassing plants, e.g. in case of vacuum tanks conceived for tap degassing and having the form of a ladle with vacuum tight cover, a vacuum hose according to the invention will have an internal diameter exceeding mm. and, in general, ranging from to 500 mm.

In case of high temperatures, and particularly with pyrophoric dusts frequent in steel degassing, particularly with higher manganese percentages of the steel, the hose according to the invention is suitably designed so as to permit protective gas to be conveyed below the external layer. For this purpose, ducts for the gas may be provided at one or both ends or between them.

In or beneath the elastic external layer, channels may likewise be laid in longitudinal direction of the hose, e.g. small hoses having outlets for the gas in their circumference. Feeding of gas, particularly of nitrogen, will cool the hose during the vacuum treatment, particularly if due to the duration of vacuum treatment the internal temperature of the hose has considerably increased.

Furthermore, feeding of the protective gas may be done in such periods of vacuum treatment, where pyrophoric dusts occur, the gas then preventing such dusts from entering through the leaks of the internal layer necessary for the flexibility of the hose. Finally, feeding of protective gas will prevent any pyrophoric dust infiltrated into the hose wall from glowing and burning due to airing of the interior of the hose.

Referring to FIGURE 2, pipe elements 11 and 12 are equipped with intermeshing spherical extremities 13 and 14. An elastic hose 16 supported by spacers 15 is pulled over the ball joint and part of each pipe element. The hose is closely pressed at its extremities by means of clips 17. Furthermore, a duct 23 for cooling gas is provided.

Referring to FIGURE 3, the pipe elements 3536 and 36-30 respectively are telescoped by their ends. One hose 31 each extending beyond the area of the telescoped pipe ends is closely pressed by means of clips 32. 34 means a spray for applying compressed air.

Pipe elements and joints are preferably made of steel or metal, particularly of a heat resistant one. Those sheaths can be rubber (up to about 200 C.) or plastics (up to about 450 C.), depending on the temperature stress in question. The vacuum tight sheaths are practically spaced from the external parts of the joints and pipe elements by rings, coils, plaits or texture or the like of heat resistant material. This will serve the purpose considering the fact that continuous layers of heat resistant material would greatly increase the weight anyhow important of the flexible lines. Using thermal insulating material such as asbestos or the like is equally possible.

As has been mentioned above, the flexible connections of the suction lines to the vacuum tank are preferably equipped with a quick coupling to reduce losses of time and, therefore, of temperature .in the vacuum tank until the beginning of casting to a minimum.

According to the invention, the vacuum hoses or flexible lines to be coupled to vacuum tanks of the aforesaid type have an adjustable support. Such support should be designed in such a way as not only to permit quick coupling and uncoupling, but also to prevent the end getting loose of the hose or the flexible line from endangering the attendance crew. The support should, therefore, assure ample stress equalization and possibly weight equalization of the free hose end. The support preferably comprises a gallows or a similar suspension.

The rope of the gallows is fastened to the hose or flexible line at one end, the other end being equipped with a drawgear or a counterweight. A resilience such as a spring or bufler, preferably at or near the connection of the rope end to the hose or the flexible line, will be suitable. The gallows or the like suspension may be a pivoted or traveling one.

FIGURES 4 and show the arrangement of quick coupling and support.

Below tap spout 41 of a (steel) melting furnace (not shown), a vacuum tap ladle 42 is placed on a traveling support 43. The ladle has a cover 44 and a downgate 45 mounted vacuum tight. Furthermore, the cover is equipped with a stationary suction stub 46. Between the end of suction stub 46 and the stationary suction line 47, there is a vacuum hose 55. Hose 55 has a suspension 50 near quick coupling 49 securing the hose to suction stub 46, rope 51 of gallows 52 being fixed to said suspension 50. The other end of the rope is provided with a drawgear 53 (or a counterweight). A resilience 54 is mounted between suspension 50 and rope 51.

As compared to FIGURE 4, FIGURE 5 is altered insofar as coupling end 57 of hose 55 hangs from above (or aslant from the above) over suction stub 46, the gallows turning about its pillar (at 56).

FIGURE 6 shows a well tried quick coupling 49 comprising flange 67 of the vacuum hose and flange 61 of suction stub 46. Between the flanges, there is a packing 62. The lower faces 63 and 63' respectively of the flanges are wedge shaped. The wedges are preferably self-releasing. They are spanned by a clamping ring provided with corresponding jaws 64 and 64' respectively. The clamping ring may be clamped and easily released by means of a quick coupling, particularly of a rolling key coupling. FIGURE 7 shows an eccentric lock 26. Clamping ring 65 has forks 69 and at its slit ends 67 and 68. Fork 69 bears joint 72 for eccentric rod 71, fork 70 serves as abutment for eccentric 73.

FIG. 8 shows a joint according to the invention using a helically wound spacer element 15.

What is claimed is:

1. A flexible vacuum hose for drawing off hot gases from evacuation vessels which comprises:

(a) A flexible metallic conduit having an exterior surface and an interior passage for the flow of said hot gases;

(b) A flexible vacuum impervious sheath surrounding the exterior surfaces of said metallic conduit, said sheath having an interior surface which is disposed in continuous spaced relation thereto so as to be thermally insulated therefrom; and

(c) Spacing means disposed between said exterior surface of the metallic conduit and said interior surface of the sheath and in abutting contact with said surfaces whereby to establish the said spacing relation therebetween which spacing means includes a plurality of metallic rings disposed at axial stations along said metallic conduit.

2. A flexible vacuum hose for drawing off hot gases from evacuation vessels which comprises:

(a) A flexible metallic conduit having an exterior surface and an interior passage for the flow of said hot gases;

(b) A flexible vacuum impervious sheath surrounding the exterior surfaces of said metallic conduit, said sheath having an interior surface which is disposed in continuous spaced relation thereto so as to be thermally insulated therefrom; and

(c) Spacing means disposed between said exterior surface of the metallic conduit and said interior surface of the sheath and in abutting contact with said surfaces whereby to establish the said spaced relation therebetween which spacing means includes a metallic helical core wrapped around the exterior of said conduit.

3. A flexible vacuum hose for drawing off hot gases from evacuation vessels, which comprises:

(a) A flexible metallic conduit having an exterior surface and an interior passage for the flow of said hot gases;

(b) An insulation liner disposed around and covering the exterior surface of said flexible conduit, the interior surface of said insulation liner being in continuous abutting contact therewith and said insulation liner being made of a heat resistant, noncombustible material, loosely packed so as to permit flexing of said metallic conduit;

(c) A flexible sheath disposed around and covering the exterior surface of said insulation liner, with the interior surface of said sheath being in continuous 5 abutting contact therewith, and said sheath being made of a vacuum impervious material; and (d) At least one coolant gas distribution duct extending into the region between the interior surface of the vacuum impervious sheath and the exterior surface of the conduit, which duct has an inlet which 5 communicates with an external coolant gas source, and a plurality of apertures for distributing coolant gas into the aforesaid region.

References Cited 10 UNITED STATES PATENTS Re. 8,994 12/ 1-879 Merriam 138-148 X 132,006 10/1872 Harris 138-138 X 376,401 1/1888 Wilder et a1. 138-131 X 15 534,473 2/1895 Harvey 138148 Berger 13832 Angeja 138139 X Peeps 138111 X Berkowitz 138139 Holmes 285-364 Nusser 138120 FOREIGN PATENTS Great Britain. France.

US. Cl. X.R. 

1. A FLEXIBLE VACUUM HOSE FOR DRAWING OFF HOT GASES FOR EVACUATION VESSELS WHICH COMPRISES; (A) A FLEXIBLE METALLIC CONDUIT HAVING AN EXTERIOR SURFACE AND AN INTERIOR PASSAGE FOR THE FLOW OF SAID HOT GASES; (B) A FLEXIBLE VACUUM IMPERVIOUS SHEATH SURROUNDING THE EXTERIOR SURFACES OF SAID METALLIC CONDUIT, SAID SHEATH HAVING AN INTERIOR SURFACE WHICH IS DISPOSED IN CONTINUOUS SPACED RELATION THERETO SO AS TO BE THERMALLY INSULATED THEREFROM; AND 